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Antivirus Performance

Third-Party Antivirus Causing Slowdown Windows 11 Fix [2026]

AG
Againly Tech Team
April 23, 2026

Third-Party Antivirus Causing Slowdown Windows 11 Fix [2026]

Quick Answer: Third-party AV slowing PC due to aggressive real-time scanning. Exclude game and work folders or switch to built-in Windows Defender.

Fix

Add Exclusions

AV Settings → Exclusions → Add folders: C:\Games, C:\Projects

Disable Real-Time Scanning

AV Settings → Real-time protection → OFF (temporary)

Schedule Scans

Set full scan for overnight, not during work hours.

Switch to Defender

Uninstall third-party AV → Windows Defender automatically enables

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Works on Windows 10 & 11 · No credit card required

Third-Party Antivirus Causing Slowdown Windows 11 Fix [2026] | Againly